The kick drum is an important part of many songs, and it has become essential to mix it properly in modern music. As one of the most important mixing tools, compression is often used to help mix the kick drum appropriately. When it comes to compressing kick drums, there are no simple step-by-step instructions; every mix is unique. However, there are certain considerations we should take into account when compressing the kick, which is what this article is all about.
Before we go any further, I should state that there are no hard rules with compression or any other mixing process. The tips mentioned in this article are simply suggestions and techniques worth considering when compressing kick drums. No procedures work 100% of the time, and every mix is unique in its own needs.
Here are 11 pro tips for compressing kick drum:
- Always A/B test
- Consider how the kick drum was recorded
- Consider the genre
- Transients and attack time
- Timing release time to the tempo of the song
- Compression for colouration
- Consider serial compression
- A note on drum bus compression
- Consider compressing kick and bass together
- Think EQ before or after compression
- Use your ears
Let's discuss each of these tips in more detail to give you important considerations when compressing kick drum in your mixes.
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Always A/B Test
Let's start off with one of the most important habits to develop in mixing: the A/B test. Before getting to any other tips, let's discuss A/Bing and bring this technique to the rest of this article's tips, shall we?
A/B testing effectively tests two options (option A and B) and compares the two to make an informed decision on which is better. We can A/B test by turning the kick drum compressor on and off (bypassing it).
Whenever we make any adjustments to a kick drum compressor, it's worth A/Bing them against the original signal and listening to whether the compression improves the sound of the kick in the overall mix or not.
When A/B testing, bypass the compressor and listen for about 10 seconds. Turn it back on and listen for another 10 seconds. Repeat the process and decide whether to keep the compressor, readjust it, or get rid of it.
The human auditory system tends to adjust to whatever we're listening to. When mixing, we can quickly lose perspective and our objective decision-making skills. As we adjust parameters to achieve balance and any other goals in the mixing process, we can quickly lose our frame of reference of what good kick drum compression actually is.
So use A/Bing to your advantage when compressing the kick drum in a mix.
If you're interested, be sure to check out my video on the top 5 A/B tests worth incorporating regularly into your mixes:
Consider How The Kick Drum Was Recorded
Generally speaking, the more information we have regarding how the song was recorded and produced, the better mixing decisions we can make. Knowing how the kick drum was recorded gives us a better idea of what it is we're working with when it comes time to apply compression (if at all).
Was the kick drum recorded with microphones, and if so, how was the kick miked up? Was the microphone placed outside or inside the kick? Was there an additional mic to capture the sound of the beater(s)?
Positioning the mic inside the kick will generally yield a boomier sound in the low-end and will be less sensitive to bleed from the other drums and cymbals of the kit (along with any other instruments in the room). Conversely, positioning a mic outside the kick will capture more bleed but perhaps a “flatter,” more natural response from the kick itself.
If a mic is positioned to capture the beater attack, we may want to lengthen the compressor's attack time to really shape the attack of the kick's sound in the top end of the mix. We can also opt to compress the main mic signal for the low-end a bit more quickly to enhance the body and sustain while taming the transients slightly. This is just a suggestion.
If there's significant bleed, we may want to hold off from applying too much compression so as not to raise the noise level relative to the kick's sound. The more we compress the loudest parts of the signal (the sound of the kick), the louder the noise (bleed) will be in relation to the kick.
Kick drums are often samples in pop, hip-hop and electronic music. Ask yourself how processed the kick drum is and whether it may or may not require compression to fit into the mix at hand.
Similarly, many productions utilize ‘drum replacement', where a recorded kick drum is either replaced or doubled with samples to enhance the sound of the drums. Regarding the kick, consider whether the original and/or replaced kick sound needs compression.
Finally, “kick drums” can also be synthesized. Be careful with synth kicks, as many synthesizers can produce frequency very defined transients. If the transient information is a bit too much, we can either shape the synth patch or utilize compression to shape the peaks of the kick attack.
Additionally, suppose the kick drum was recorded with compression inserted between the mic and the recording medium (digital or analog). In that case, we may not need as much compression in the mix, if at all.
I don't have any specific settings for compression in this regard. However, it's important to know the source of the kick drum sound to make more informed decisions.
Consider The Genre
Kick drums often serve different roles, albeit slightly, in different genres of music. Furthermore, the typical mix aesthetic tends to shift from genre to genre.
We'll often record or sample a kick drum to suit the song in the recording and production phases of the music production process. However, it's worth considering the genre and the role of the kick drum within the song before we reach for compression.
I should reiterate that no two mixes are the same, but we can still draw similarities within genres.
For example, the kick drum of an EDM track will likely be much more powerful and well-represented in the mix. A jazz kick may be lower in the mix and not require compression at all. A steady 32nd note kick pattern in a metal song may require significant shaping (with compression or otherwise) in order not to overload the low-end of the mix.
These examples are just a few of the considerations worth addressing. Give thought to the genre of music you're mixing and study a few references if you need to to get a better idea of potential compression moves on the kick drum.
Transients And Attack Time
A compressor is designed to reduce or “compress” the dynamic range of an audio signal by applying gain reduction to the peak levels of that signal.
However, compressors don't act instantaneously to such peaks, and we actually have an opportunity to increase the dynamic range or, at the very least, shape the transients of our kick drum in the mix.
This is done primarily by altering the time parameters of the compressor and, more notably, the attack time.
The attack time is the amount of time it takes for a compressor to engage/react once the input signal amplitude surpasses the threshold. It's a rate of change whereby the compressor gradually reaches its full ratio over time. It's not a delay of action, where the compressor will clamp down fully after a set period of time.
With fast attack times, the compressor can clamp down quickly on the transient information and effectively reduce the peak levels of the signal. When done subtly, this can help thicken the kick drums and maintain a more consistent level and sustain. However, when overdone, it can have the effect of dulling the punch of the kick and crushing the dynamics.
With slower attack times, the compressor will react more slowly to the transient information and actually allow some of the transient peaks through uncompressed before clamping down on the signal level. When dialled in correctly, we can shape the dynamics of the kick to suit the mix better.
Pay special attention to the attack of the kick. The transients are super important in percussion instruments and because the kick is often the “heartbeat” of the song, having it dialled in properly in terms of its transients/attack is paramount.
For more information on transient shaping with compression, check out my video:
Timing Release Time To The Tempo Of The Song
We just discussed the power of compression attack times. Now let's discuss the other time parameter: the release time.
The release time is the amount of time it takes for the compressor to disengage (to stop attenuating the signal) once the input signal drops below the threshold. Like the attack time, it's a rate of change whereby the compressor gradually disengages over time. It's not a delay of action, where the compressor will suddenly stop compressing after a set period of time.
By timing the release time to the tempo of the song, I mean setting the parameter so that the compressor typically disengages fully just before the next transient in the kick drum track (the next time the kick hits).
Of course, this is easier said than done if we have anything other than a four-to-the-floor groove. However, even if the kick drum is playing more complex rhythms, having the compressor disengage before the major beats can work wonders for improving the “naturalness” of the compressor.
It can even add a bit of extra groove in complex patterns by almost undermining the kick hits in between the main beats (if the compressor isn't fully disengaged before a “less important” kick, it will effectively have a starting point of some amount of gain reduction).
For one, it reduces the amount of perceived “pumping” caused by rapid changes in gain reduction. It can also help improve the perceived sustain of the kick drum by maintaining a more consistent level as the compressor slowly disengages and the original signal level drops simultaneously.
Compression For Colouration
In addition to the main purpose of automatic gain reduction, compressors will have the effect of colouring the sound. While some compressor plugins are programmed to be as transparent as possible, many other plugins, and certainly hardware compressors, will impart their own sonic imprint on the audio signals passing through them.
This colouration is sometimes experienced as an inherent EQ curve, though perhaps more obviously, it's experienced as harmonic saturation, where new harmonic information is effectively added to the signal due to the distortion of the components (or programming) of the design.
Such colouration can help enhance the kick drum's character and help it “poke through” the mix, particularly in the upper mid-range around its beater attack frequencies.
Utilizing compression for its characteristic “sound” is relatively common, even if it means inserting a compressor in-line without even applying any gain reduction only to add colour to the kick (or other elements).
One issue to consider is the inherent noise caused by hardware compressors and analog plugin emulations. We must ensure proper gain staging to achieve a solid signal-to-noise ratio. This means we need to drive the compressor with enough signal level to avoid excessive noise relative to the signal while also keeping the signal level low enough to avoid excessive distortion.
On top of the inherent sonic characteristics of certain compressors, the actual gain reduction applied by the compressor will also obviously alter the sound. In this way, we can also apply subtle amounts of compression to add a bit of extra character to the kick drum.
Consider Serial Compression
Serial compression, as the name suggests, has multiple compressors in series in a signal chain. In other words, having a compressor's output feeding another compressor's input (and so on) somewhere down the line.
Serial compression could be as simple as inserting two compressors on a single kick track or having a single compressor on a kick track being routed through a drum bus (also being compressed) that's ultimately being fed through a mix bus compressor.
To keep things simple for this article, we'll discuss compressors inserted back-to-back on a single kick drum track.
Serial compression, in this way, is great for not overloading any single compressor. It can sound more natural and shave off more dynamics, leading to more consistent kick drum levels without as many unnatural pumping artifacts. We can also get different colours of different compressors (see the previous tip).
Imagine pushing 12 dB of gain reduction on a single compressor. Chances are the kick will sound pretty “squashed” or experience significant “pumping”. Either way, it's liable to sound unnatural.
The transient information will likely suffer along with the sustain. Although it can be done in some mixes, it's typically a losing battle attempting to get that much gain reduction without these negative side effects.
However, if we were to utilize two compressors to compress 6 dB of gain reduction each, we'd be able to get more natural results. The first compressor would tame the peaks, and the second would help round out the sustain and maybe even add punch.
Try this out for yourself the next time you need a significant amount of kick drum compression to fit a kick in the mix appropriately.
A Note On Drum Bus Compression
Beyond compressing the kick drum track, we should also consider the kick drum's role in the drum bus (if we're routing the kick to a drum bus) and how we may want to go about compressing the drum bus.
Subtle glue compression can help bring the individual drum tracks together into a more cohesive-sounding kit. To achieve this style of compression, start with a low ratio of 2:1, a high threshold with about 1 or 2 dB of gain reduction, and medium attack and release times. Adjust the parameters to find a setting that glues the drums together nicely.
You can also opt to send drums to a bus for parallel compression processing. Parallel compression generally crushes the bus signal (high ratio with lots of gain reduction) and mixes it back in with the rest of the mix at a lower level.
These are only suggestions, and you should adjust as necessary.
Note that, when it comes to the drum bus, the low-end energy of the kick drum can be the first (and potentially the only) part of the signal to trigger the compressor's gain reduction. This is especially the case if the kick is particularly well represented in the drum bus.
When this is the case, we can opt for a compressor that has a high-pass filter in its sidechain signal path. This way, we can reduce or eliminate the effect that the low end of the kick drum will have on the compressor's gain reduction circuit/program.
With less (or no) reaction to the low-end frequencies of the kick, we can often get more consistent compression of the drum bus with less pumping due to the kick drum.
In many cases, we won't have to worry. However, in the cases where the kick triggers the drum bus compression too much, we can opt to high-pass filter the sidechain signal. Set the HPF to taste.
Consider Compressing Kick And Bass Together
Mixing the kick drum and the bass elements of a song so they work well together can be challenging in many mixes. There are plenty of strategies to help mix the kick and bass symbiotically, and one potential technique worth trying out is actually compressing them together.
Of course, this takes a turn from the previous tip on drum bus compression. Rather than feeding the kick drum to the drum bus, we'll be bussing the kick and bass to their own bus. The rest of the drums can still be routed to a proper drum bus (minus kick).
After spending time honing in the separation between the kick and bass (with sidechain compression, mirrored EQ, high-pass filtering other elements, saturating the bass, etc.), it can be beneficial to “glue” them together with compression to help them sit even more cohesively in the mix.
Glue is the sense/perception that sounds belong together and exist within the same world in the mix.
This “glue compression” is one of several ways to make grouped track or, indeed, the entire mix sound more cohesive, which is the ultimate goal of mixing to begin with.
This happens because the compressor can be triggered by a single track (typically the transient of the kick drum track(s)) but affect all the other elements in the mix (the bass guitar track(s)). This simple relationship can help tie the kick and bass guitar together and improve cohesion in the mix, particularly in the low end.
Try this out by bussing the kick drum and the bass guitar together and compressing the bus. Even a subtle amount of compression can really glue these two important low-end elements together in the mix.
Think EQ Before Or After Compression
Compression and EQ are two of the most-used processes in mixing, so it's worth addressing whether to compress the kick drum before or after EQ (or both).
If any notable resonances or low-end noise in the kick drum signal could trigger the compressor, I would filter those frequencies out with EQ before sending the kick drum signal to the compressor.
Beyond that, it's largely a matter of taste. However, I'd still recommend investigating which order sounds best in your specific mix.
EQing a kick drum before compression lets us shape the frequency content more aggressively, knowing that the compressor will help smooth it out. It's also good to have control over what the compressor “sees” and reacts to.
In general, EQ before compression will yield a smoother, warmer result with kick drums (and other sources).
Compressing a kick drum before EQ gives us less control over what the compressor reacts to but more control over the tonal balance of the signal. Note that the EQ should be applied more sparingly here since the audio has already been smoothed out.
In general, EQ after compression offers a cleaner, sharper result with kick drums (and other sources).
So consider the genre and the song as a whole, and experiment with whether the compressor should come before or after the EQ if either process is used at all!
Use Your Ears
Okay, perhaps this tip is a bit too obvious, but it's vital that we use our ears when using any processing on any tracks within a mix. This, of course, includes kick drum compression.
Any tips I could give you in this article are null and void if they don't serve your tastes or the mix as a whole. It's impossible to give instructions about specific parameter settings because every mix will demand something different.
While I can give you good starting points and general advice, the best piece of advice I could ever give you when compressing a kick drum is to use your ears.
If the kick drum compression doesn't sound good or serve the mix, either get rid of it, change the compressor being used, or adjust the parameters of the current compressor. Rely on your ears (along with A/B testing) to get the best results!
Other Compression Tips For Common Elements
- Top 10 Best Tips For Compressing Snare Drums
- Top 11 Best Tips For Compressing Bass Guitar
- Top 9 Best Tips For Compressing Electric Guitars
- Top 9 Best Tips For Compressing Acoustic Guitars
- Top 9 Best Tips For Compressing Pianos & Keyboards
- Top 11 Best Tips For Compressing Vocals
- Top 11 Best Tips For Compressing The Mix Bus
Be sure to also check out my top overall 11 compression tips for mixing in this video: